Expected EAGLE Event Rate towards the Magellanic Clouds

We propose to search for MACHOs by observing EAGLE (Extremely AmplifiedGravitational LEnsing) events of a majority of dim stars. This search isindependent of the usual one. For the detection limit of EAGLE (about 20 mag),about 100 f (\tau^{LMC} / 3 \times 10^{-7}) (100 days / ) EAGLE events/y areexpected to result from all the dim stars in LMC. Here \tau^{LMC} and arethe optical depth and the average duration of microlensing events,respectively, while f (0 < f < 1) is a parameter depending on the unknownstellar luminosity function. The observed mean duration of EAGLE events alsodepends on the luminosity function and is (0.01 - 0.4) times the usual durationof microlensing events, which corresponds to (1 - 30) days. The follow-upobservation using larger telescopes may enable us to determine the impactparameter and the true duration of the event. If f is determined by anotherindependent method, we can also determine \tau^{LMC}. Even if f isundetermined, the detection of EAGLE events strongly suggest that MACHOs arenot due to variable source stars, since EAGLE events are due to the dimmain-sequence stars. Although for the SMC, the event rate is smaller by afactor of about 7, it is still a substantial number (about 13 f (\tau^{SMC} / 3\times 10^{-7} (100 days / ) events/y).Comment: 8 pages, Prog. Theor. Phys. in pres